Field of the Invention
The present invention relates to tire molds.
Description of the Related Art
JP2013-144414 discloses a tire mold. The mold includes multiple tread segments (hereinafter, referred to as segments) and a pair of side plates. In a tire vulcanization step, an unvulcanized raw cover (green tire) is prepared. The raw cover is put into a mold. The raw cover is pressurized and heated in the mold, whereby a tire can be obtained from the raw cover.
In this vulcanization step, the multiple segments are arranged in the circumferential direction so as to form a ring shape. Each of the side plates contacts with the multiple segments forming the ring shape. The multiple segments and the pair of side plates form a cavity for molding a tire. A tread surface of the tire is formed by the multiple segments, and sidewall outer surfaces of the tire are formed by the pair of side plates.
In the tire vulcanization step, a rubber composition of the raw cover flows by being pressurized and heated. In the mold having a gap between the segments and the side plates which contact with each other, the rubber composition flows into the gap. Similarly, in the mold having a gap between the segments which contact with each other in the circumferential direction, the rubber composition flows into the gap. The rubber composition having flowed into the gaps forms a so-called overflow spew (rubber spew) on the outer surface of a tire.
The mold is repeatedly used. As a result of the repeated use, wear of the contact surfaces of the segments and the contact surfaces of the side plates progresses. This progress of wear increases a gap between the contact surfaces. In the mold having a large gap, large overflow spew may be generated. The overflow spew deteriorates the outer appearance of the tire.
An object of the present invention is to provide a tire mold for molding a tire having an excellent outer appearance.